Let me try again, only when the account holder's spouse is not the beneficiary.

I believe the spouse is supposed to agree to all beneficiary changes. You can't for example reduce your spouse's share beneficiary percentage without consent.

But what do I know, I am not legally married. And the California RDP my partner and I plan on having this year won't be federally recognized anytime soon. So I guess he may have no say over my 401k beneficiary elections. Even though some of the income that funds it will be considered community property under California law.